Photography is an immensely popular activity. The works of professional still-picture photographers are illustrated everyday in newspapers, magazines, and advertisements, and the works of professional moving-picture photographers are present in television and films. Countless amateur photographers take pictures to capture many life's events. Further, with recent technological advances in cameras, along with accompanying price drops, even the most mundane activities and events are now recorded.
An early problem encountered in photography was glare directly from the Sun or by way of reflective objects. A small portion of sunlight is polarized when it passes through our atmosphere. The atmospheric haze as well as the polarized light reflected by objects cause glare that is then recorded in images taken by still-picture or video cameras. In some cases, this glare may be undesirable and can adversely affect the clarity of the taken images.
To address the problem of unwanted glare, certain types of polarized filters are used in photography to reduce glare. A portion of the light received from the sun is polarized generally in the horizontal direction. Most polarized filters used on cameras have a vertical polarization axis, i.e., they are configured to pass light polarized in the vertical direction, and block light polarized in the horizontal direction. Accordingly, these polarized filters can remove some of the atmospheric haze and reflected sunlight, leading to a reduction in unwanted glare.
However, the use of polarized filters does not protect well against glare emanating from most man-made light sources, such as camera light sources including flash sources and spot light sources. Light from a flash or lamp is typically not polarized. When light from a camera is reflected off a reflective object, such as a window, mirror, or even skin, it is not polarized. Accordingly, camera polarized filters cannot effectively reduce glare caused by most man-made light sources. Thus, the image taken is susceptible to impaired image quality due to glare emanating from camera light sources.